Separation layer method for the flat coating of smooth surfaces (straight or curved) with self-adhesive foil

ABSTRACT

Process of applying a self-adhesive film to a surface of an automobile or other vehicle. Later removal of the film is facilitated by first applying a parting layer to the surface, except for surface regions being covered by the perimeter and certain other areas of the self-adhesive film.

DESCRIPTION

The generally used method for aiding in the application of self-adhesivefilms to large surfaces without air bubbles or wrinkles consists ofmoistening the surface to be coated with water (usually treated withdetergent or a similar surfactant); this strongly reduces the initialtack of the film applied thereto; the piece of film can still beadjusted to fit exactly. Air bubbles and water are smoothed out with adoctor blade.

This method is not suitable for the coating/adhesive covering ofcontoured and nonhorizontal surfaces: At contours, edges, compoundcurves, etc., the film is stretched, or deformed with the use of a heatgun; in these areas, the film must immediately adhere with fulladhesion, so that it does not revert to its original shape. Water usedas a parting layer on contoured and nonhorizontal surfaces would not befixable (it runs) and would reduce or impair the adhesion of the film inthose areas in which full adhesion is necessary.

Manufacturers of self-adhesive films, for their part, attempt to reduceinitial tack and allow for the smoothing out of residual air pocketsunder the film through the composition of the adhesive or by means ofadditions to the adhesive:

a layer of extremely fine glass beads on the adhesive layer creates akind of spacer; only after pressure from the doctor blade are the beadspressed into the adhesive, which then develops its full adhesivestrength;

the composition of certain adhesives is designed so that their level ofadhesion is initially low, yet increases after a certain interval oftime.

The drawbacks of these methods lie in their relatively complicatedmanufacture and the associated costs.

The goal consisted of developing a separating method that fulfillsseveral requirements:

It must be possible to apply the self-adhesive film to the surface to becovered with a low initial tack, so that exact positioning is possible(one must be able to remove it, correct its position, and reapply iteasily);

the parting agent must be easy to apply;

the parting agent must not run and must allow for its application in aflat coat to smooth surfaces, also contoured, uneven, and nonhorizontalones, as required by the user;

the use of the parting agent must allow the removal of air bubbles whichremain under the film during application through smoothing with a doctorblade;

the full adhesion of the film shall act only on the perimeter of eachsurface (exception: areas, in which the film was deformed and also needsgreat adhesion). The adhesion of the film on the balance of the surfaceareas shall be reduced, to facilitate the later removal of the film.

Through the use of the method of the present invention theserequirements can be met:

Oils/greases or substances containing oils/greases reduce the initialtack of the film adhesive; the newly applied piece of film can easily betaken off again and correctly reapplied;

at the proper temperature the above substances can be easily applied tothe surfaces which are to be coated;

because of their viscosity, they cannot run;

air pockets under the adhesive film can be smoothed out to the edge ofthe coated surface;

the reduced adhesion that results from the application of the partingagent disclosed herein onto the appropriate surface areas allows for theeasier removal of the film coating later;

EXAMPLE OF USAGE

The method described herein can be used primarily for the completesurface coating of passenger cars, specifically for taxis.

Here the vehicles whose exterior color is dictated by law according totheir use in the transportation industry are completely covered withself-adhesive film of the required color. Upon sale of the vehicle, thefilm is removed. The technique of film covering allows color-neutralvehicle purchases for taxi companies and thereby also increases theresale value of the vehicles.

The use of the method described herein facilitates the attachment of thefilm covering and its later removal.

BRIEF DESCRIPTION OF THE DRAWING

The FIGURE illustrates a vehicle door covered with a parting agent,according to a preferred embodiment of the present invention.

Application of parting agent, such as a mineral oil or grease, syntheticoil or grease or a fluid or creamy product that contains oil or grease,onto a vehicle door to be covered with self-adhesive film: the perimeterof the door surface, the groove, and the door handle depression wereavoided in the otherwise surface-coating application of the partingagent, since 100% adhesion is required in these areas; on the balance ofthe surface the adhesion of the film is reduced, which makes removal ofthe film coating easier.

What is claimed is:
 1. A method for the application of self-adhesivefilms onto a surface of an automobile of any kind, wherein: prior toapplying the self-adhesive film to the vehicle, a parting agent isapplied to the surface except for regions to be covered by the perimeterand certain other areas of the film, so that full adhesion of theself-adhesive film in the perimeter and the certain other areas is notimpaired while adhesion in remaining areas of the surface is reduced,thereby facilitating later removal of the film from the surface.
 2. Amethod as in claim 1, comprising: using a parting agent comprisingmineral oil or grease, synthetic oil or grease, or a fluid or creamyproduct that contains oil or grease.